Determination of the decarburation depth

Presentation for participants

 
Reference of the ILC: DC-X-LS
   
References of test methods: ISO 3887  ASTM E1077                  
   
Frequency: For this ILC, there is a risk that the number of registrations is insufficient. So a pre-registration procedure is put in place, as follows:
  1 - Participants interested in participating pre-register using the registration form. No invoicing is made for this pre-registration;
2 - When at least 10 potential participants have pre-registered, CompaLab asks each of these pre-registrees to confirm their willingness to participate and what are the characteristics for which they commit to provide results;
3 - If at least 8 participants confirm their intention to participate, the CIL organisation concerned is engaged.
   
   
Main characteristics: d₁ (total decarburization), d₂ (functional decarburization), d₃ (partial decarburization), d₄ (global decarburization)
   
Other characteristics: Surface carbon content, heart carbon content, surface hardness, heart hardness
  Caution: The number of determinations may be low for the secundary characteristics, what may make inefficient the comparison between laboratories
   
   
Determination of the assigned values (“true values” for each characteristic): By statistical computation of the totality of the results with possible selection on competence criteria (accreditation, validation by a reference body, quantity of tests performed in the year), test to detect possible collusion, merging of results not obtained in reproductibility conditions, suppression of technically unvalid results.
   
Type of statistical computation: For numerical results, the statistical computation will provide an assigned value with its attached uncertainty, values of standard deviations for repeatability and reproductibility, limits of alerts for bias and repeatability of the participant, indiviual values for uncertainty of results of participants.
Number of products submitted to tests: 1
Number of samples per participation: 6
Max number of operators per participation: 10 (For this CIL, the type of test and sample size allow to provide results determined by several different operators)
Product submitted to tests: Low alloyed steel
Type of samples: Discs
Approximate dimensions of samples: Ø40x50 mm
Specific preparation to be performed by the participant:  Preparation of surfaces of observation
                   
Special notice for this ILC: Determinations of d₁, d₂, d₃, d₄ can be performed with the 3 methods : metallographic, chemical and/or hardness